1. Field of the Invention
The present invention relates to an air pressure managing system for an electronic equipment installed in a room having a door. More particularly, the present invention relates to an air pressure managing system for an electronic equipment installed in a room having a door, in which the electronic system can be managed with improved efficiency without harmful influence of much noise, or excessively high electric power.
2. Description Related to the Prior Art
There is a digital printing service in which a digital printer, for example thermal printer, is used in a room or a commercial space, for example in a convenience store or other shops. According to this, a memory card is used, in which digital image data is stored. The memory card is set in the digital printer. A display panel of the digital printer displays a command menu. A user or customer views the menu, and operate the digital printer to produce prints with image according to his or her digital image data.
Specifically at a convenience store as an environment with much pedestrian traffic of customers, there occurs external dust or particles entering the room at a considerable amount. It is very likely that dust comes to remain in the digital printer as electronic equipment that is installed in the room. If a shop owner or attendant fails to check and maintain the digital printer for a long time, the dust in the digital printer increases to a harmful extent. Image quality of prints may be lowered because the dust may cause failure or breakage of the digital printer. To solve such problems, there is a suggestion in JP-A 2001-010166 in that an external air sending fan is incorporated in the digital printer, sends air to the inside of the digital printer to heighten the air pressure inside the digital printer. Thus, entry of external dust is prevented in the digital printer.
However, there are excessive changes in the traffic of the customers between time zones during the business hour of the retail shop. If the external air sending fan is actuated incessantly to keep the air pressure high, the operation of the external air sending fan is ineffective typically in a time zone with very small traffic of customers. Noise in rotation of the external air sending fan may be heard in an unwanted manner. Electric power used in such a time zone may be too high.
In view of the foregoing problems, an object of the present invention is to provide an air pressure managing system for an electronic equipment installed in a room having a door, in which the electronic system can be managed with improved efficiency without harmful influence of much noise, or excessively high electric power.
In order to achieve the above and other objects and advantages of this invention, an air pressure managing system for an electronic equipment installed in a room having a door for closing a door opening in an openable manner is provided. A door state signal generator monitors a state of the door, and outputs an open signal when the door is open. An air pressure adjustor is actuated in response to outputting the open signal, for adjusting pressure of air in the equipment, to prevent the equipment from being influenced by air flowing from outside the door opening.
The air pressure adjustor prevents dust from spreading in the equipment, to keep an inside of the equipment clean, the dust having flowed with the air flowing from outside the door opening.
The air pressure adjustor is secured to the equipment, and the equipment is connected with the door state signal generator by a network.
Furthermore, a timer measures elapsed time elapsed after the air pressure adjustor stops. When the elapsed time comes up to a predetermined standby time, the air pressure adjustor operates for dust prevention in a standby sequence.
Furthermore, inner and outer opener switches or opener sensors detect an object or human body located respectively in front of and behind the door opening, to output a detection signal. A door driving mechanism is turned on when the detection signal is output, to open the door opening by moving the door in an open direction.
The air pressure adjustor includes a fan or blower for sending the air from outside the equipment toward an inside thereof.
The fan or blower, while the open signal is output, sends the air in a high level mode, and before start of outputting of the open signal and after discontinuation of outputting of the open signal, sends the air in a low level mode in which a flow rate of the air is smaller than in the high level mode.
While the fan or blower operates in the high level mode and when the door is closed, the door state signal generator discontinues outputting of the open signal. The timer measures elapsed time elapsed after discontinuation of the open signal. When the elapsed time comes up to a predetermined driving time, the fan or blower sends the air in the low level mode.
The fan or blower rotates at a lower rotational speed in the low level mode than in the high level mode.
According to another preferred embodiment, the air pressure adjustor, while the open signal is output, continuously operates for dust prevention, and before start of outputting of the open signal and after discontinuation of outputting of the open signal, intermittently operates for dust prevention.
While the air pressure adjustor operates and when the door is closed, the door state signal generator discontinues outputting of the open signal. The timer measures elapsed time elapsed after the outputting of the open signal discontinues. The air pressure adjustor, when the elapsed time comes up to a predetermined driving time, stops, and when the elapsed time subsequently comes up to a predetermined limit time, operates for dust prevention in a standby sequence.
The timer measures elapsed time elapsed while the air pressure adjustor operates in the standby sequence. When the elapsed time comes up to a predetermined operating time, the air pressure adjustor stops from operating.
The equipment is a printer.
The door state signal generator is a photo sensor.
In another aspect of the invention, an air pressure managing system includes a door state signal generator for monitoring a state of the door, and for outputting an open signal when the door is open. A protecting device is actuated in response to outputting the open signal, for protecting the equipment from being influenced externally through the door opening.